山羊视网膜节细胞的形态学类型及其分布特点

MORPHOLOGICAL TYPES AND DISTRIBUTION CHARACTERS OF RETINAL GANGLION CELLS IN THE MILK GOAT

利用荧光染料DiI逆行标记技术、激光共聚焦扫描技术和计算机图像处理方法,对北京奶山羊视网膜节细胞(RGCs)的形态学类型及其分布特点进行了系统研究。根据其细胞体的面积和树突野的大小,山羊RGCs分为RGA型(大细胞体和大树突野)、RGB型(小细胞体和小树突野)、RGC型(中小型细胞体和中大型树突野)3种细胞类型。然后根据树突分支特征和细胞体在RGCs中的位置,又将RGCs分为更多亚型(RGA1、RGA2、RGB1、RGB2、RGB3、RGC1、RGC2、RGC3、RGC4)。不同类型的RGCs在视网膜中央区和周边部出现的频率不同,在中央区以小型树突野的RGCs为多,占82%,大型树突野的RGCs仅占5.5%;而在视网膜周边部,尤其是颞侧周边部小型树突野的RGCs比例明显减少(42.5%),大型树突野的RGCs比例增多,尤其以RGA型增加的最为明显(33.4%)。结果表明,山羊视网膜中央区有优越的视力且在解析空间情报方面占优势;而在视网膜周边部则在解析时间情报方面占优势。

The morphological types and distribution characters of retinal ganglion cells （RGCs） were studied in the Beijing milk goat using methods of retrograde labeling of carbocyanine dye （ Dii）. confocal laser scanning microscope and image analysis by the computer. The RGCs of goat were classified into 3 types ： RGA （ large scmata and dentritic field）, RGs （ small somata and dendritic field） and RGc （ small to medium-sized somata and medium to large dendritic field）. On the basis of dendritic field morphology and presence across the RGCs dendrites, each group was then subdivided into more subgroups： RGA1, RGA2, RGB1 , RGB2, RGB3, RGC1, RGC2, RGC3, RGC4. The proportion of each subtype that presents in the central retina and peripheral region was different. In the central retina, the proportion of small type RGCs was 82% ,but the large dendritic field RGCs was only 5.5%. In the peripheral region, especially in temporal periphery, the proportion of small type RGCs was obviously decreased （42.5%） ,the large dendritic field RGCs were much more than that in the central retina,especially the RGA type （33.4%）. The results show that the central area displays the higher visual acuity and time information resolution, while the peripheral zones gain advantage over spatial information resolution.